Transportable High Vertical-Lift Emergency Water Pumping System

ABSTRACT

A transportable high vertical-lift emergency water pumping system moves emergency water from a water source at a low elevation to a higher elevation. The pumping system has a first pump having a first-pump suction port at the higher elevation and a second pump having a second-pump suction port at the low elevation and a second-pump discharge port in fluid communication with the first-pump suction port. A variable speed driver is operatively coupled to the first pump. A load sensing hydrostatic drive system is operatively coupled to the variable speed driver and to the second pump. The load sensing hydrostatic drive system is configured to maintain a minimum net positive suction head at the first-pump suction port sufficient to prevent cavitation in the first pump when the variable-speed driver operates at any speed of a plurality of speeds across a range of flows.

BACKGROUND OF THE INVENTION

The present invention relates to a transportable water pumping systemfor emergency applications. More particularly, the present inventionrelates to high vertical-lift water pumping systems able to moving waterfrom a water source such as a lake or river at a low elevation to ahigher elevation for emergency use in situations such as fire fightingor cooling after a disaster has taken out all power and supportinfrastructure.

Often, the main way to extinguish a fire is to spray the base of thefire with massive volumes of water to asphyxiate the flames and cool thecombustible material and the surrounding area Water for fighting a firemay be accessed from various sources, such as from a pressurized firehydrant, pumped from water sources such as lakes or rivers, or deliveredby tanker truck. In instances when the source of water is a body ofwater in a location with difficult access, it may not be practical toplace pumping equipment entirely proximal to the source of water.

Accordingly, there is a need in certain emergency situations for atransportable high vertical-lift water pumping system able to draw waterfrom a water source at a low elevation to extinguishing fires at ahigher elevation or to cool structures at a higher elevation containinghazardous materials.

BRIEF SUMMARY OF THE INVENTION

Briefly stated, one embodiment of the present invention is directed to atransportable high vertical-lift emergency water pumping system formoving emergency water from a water source at a low elevation to ahigher elevation. The pumping system has a first pump having afirst-pump suction port at the higher elevation and a second pump havinga second-pump suction port at the low elevation and a second-pumpdischarge port in fluid communication with the first-pump suction port.A variable speed driver operatively couples to the first pump. A loadsensing hydrostatic drive system is operatively coupled to the variablespeed driver and to the second pump. The load sensing hydrostatic drivesystem is configured to maintain a minimum net positive suction head atthe first-pump suction port sufficient to prevent cavitation in thefirst pump when the variable-speed driver operates at any speed within arange of flows.

Another embodiment of the present invention is directed to a method formoving emergency water from a water source at a low elevation to ahigher elevation relative to the water source. The method comprises thefollowing steps: (i) drawing water from the water source into a suctionport of a hydraulically driven submersible pump in the water source;(ii) discharging the water from a discharge port of the hydraulicallydriven submersible pump into a lay-flat hose connecting the dischargeport of the hydraulically driven submersible pump to a suction port of afire pump at the higher elevation; and (iii) maintaining a minimum netpositive suction head at the fire-pump suction port sufficient toprevent cavitation in the fire pump when the water is discharged from adischarge port of the fire pump at any flow rate within a range of flowrates.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofpreferred embodiments of the invention, will be better understood whenread in conjunction with the appended drawings. For the purpose ofillustrating the invention, the drawings show embodiments which arepresently preferred. It should be understood, however, that theinvention is not limited to the precise arrangements andinstrumentalities shown.

In the drawings:

FIG. 1 is a schematic diagram of a first preferred embodiment of atransportable high vertical-lift emergency water pumping system inaccordance with the present invention;

FIG. 2 is a schematic of a prior art load sensing hydrostatic drivesystem suitable for use in the pumping system of FIG. 1; and

FIG. 3 is a functional flow diagram for the pumping system of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to embodiments of the invention,examples of which are illustrated in the accompanying drawings. Theterminology used in the description of the invention herein is for thepurpose of describing particular embodiments only and is not intended tobe limiting of the invention.

As used in the description of the invention and the appended claims, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. The words“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

Although the words first, second, etc., are used herein to describevarious elements, these elements should not be limited by these words.These words are only used to distinguish one element from another. Forexample, a first pump could be termed a second pump, and, similarly, asecond pump could be termed a first pump, without departing from thescope of the present invention.

The following description is directed towards various embodiments of apumping system in accordance with the present invention.

Referring to the drawings in detail, where like numerals indicate likeelements throughout, there is shown in FIG. 1 a first preferredembodiment of the a transportable high vertical-lift emergency waterpumping system, generally designated 100, and hereinafter referred to asthe “pumping system” 100 in accordance with the present invention. Thepumping system 100 is for moving emergency water from a water source ata low elevation such as a lake or river to a higher elevation at whichstructure requiring the emergency water is located. Various embodimentsof the present invention can be configured to accommodate a wide rangeof differences in elevation such as about 35 ft to 150 ft. However, thedifference in elevation that some embodiments of the present inventioncan accommodate is not limited to the range of about 35 ft to 150 ft.

The pumping system 100 comprises a first (or main) pump 102 at thehigher elevation and a second (or auxiliary) pump 104 at the lowerelevation. The first pump 102 has a first-pump suction port 102 s and afirst-pump discharge port 102 d, both of which are at the higherelevation. The second pump 104 has a second-pump suction port 104 s anda second-pump discharge port 104 d, both of which are at the lowelevation. The second-pump discharge port 104 d is in fluidcommunication with the first-pump suction port 102 s. In someembodiments of the pumping system 100, the first pump 102 has afirst-pump efficiency and the second pump 104 has a second-pumpefficiency less than the first-pump efficiency. Suggestedly, the firstpump has an efficiency of at least about 60%, desirably 70% or more, andpreferably between about 70 to 75, for a head about 150 to 250 psi and aflow of about 500 to 3000 gallons per minute and the second pump has anefficiency at least about 50%.

In some embodiments of the pumping system 100, the first pump 102 is afire pump, the second pump 104 is a submersible hydraulic driven pumpand the first-pump suction port 102 s is directly connected to thesecond-pump discharge port 104 d by a lay-flat hose 103. In otherembodiments, the second pump 104 may be a floating hydraulically drivensubmersible pump. In still other embodiments, the second pump 104 may bean electrically driven submersible pump. In even other embodiments, thesecond pump 104 may be paired with a third pump (see, FIG. 2) having athird-pump suction port at the low elevation and a third-pump dischargeport in fluid communication with the first-pump suction port 102 s. Insome embodiments, the second and third pumps may independently be turnedon or off so that either the first pump or the second pump or both thefirst pump and the second pump may be used to increase lift or flowcapacity.

The pumping system 100 has a variable speed driver 106 operativelycoupled to the first pump 102. In some embodiments, the variable speeddriver 106 may be a diesel engine operatively coupled to the first pump102 is by a gear assembly 108.

A load sensing hydrostatic drive system 110 is operatively coupled tothe variable speed driver 106 and to the second pump 104. The loadsensing hydrostatic drive system 110 is configured to maintain a netpositive suction head at the first-pump suction port 102 s sufficient toprevent cavitation in the first pump 102 when the variable-speed driver106 operates at any speed of a plurality of speeds across a wide rangeof flows. Suggestedly, the variable-speed driver 106 operates at a speedof at least about 1800 rpm, desirably 2000 rpm or more, and preferablybetween about 1900 to 2100 rpm, for a first pump net positive suctionhead about 5 to 10 psi and a flow of about 500 to 3000 gallons perminute .

In some embodiments of the pumping system 100, the load sensinghydrostatic drive system 110 comprises at least one hydraulic pump 112in fluid communication with a hydraulic motor 114 and a load sensingcontroller 116. The hydraulic pump 112 may be operatively coupled to thevariable-speed driver 106 by the gear assembly 108 and the hydraulicmotor 114 may be in fluid communication with the second pump 104.

A representative schematic for a load sensing hydrostatic drive systemmanufactured by HYDRA-TECH Pumps, Nesquehoning, Pa. for dual submersiblepumps is shown in FIG. 2. The, components in the schematic designatingby the reference numbers appearing therein are identified in thefollowing table:

TABLE 1 Ref. No. Component 1 Oil Reservoir, (2) 60 Gallon Sections 2Suction Strainer 3 Pressure Compensated, Load Sensing Hydraulic Pump 4Diesel Engine 5 Maximum Flow Control (Adjustable) 6 Restrictor Orifice 7Pressure Gauge 8 Solenoid Valve, N.O. 9 Hose Reel with Live Swivels 10Quick-Disconnect Coupling 11 Hydraulic Motor 12 Hydraulic Oil Coolerw/Cold Oil By-Pass Valve 13 Return Filter w/By-Pass Valve and PressureSwitch

In some of the foregoing embodiments of the pumping system 100, thecomponents may be assembled in a configuration mountable on a mobileplatform.

Referring to FIG. 3, in use, the pumping system 100 moves emergencywater from a water source at a low elevation to a higher elevationrelative to the water source in the following manner.

In a drawing step S1, water from the water source is drawn into thesuction port a hydraulically driven submersible pump in the watersource.

In a discharging step S2, the drawn water is discharged from a dischargeport of the hydraulically driven submersible pump into a lay-flat hoseconnecting the discharge port of the hydraulically driven submersiblepump to a suction port of a fire pump at the higher elevation.

In a maintaining step S3, a minimum net positive suction head ismaintained at the fire-pump suction port sufficient to preventcavitation in the fire pump when the water is discharged from adischarge port of the fire pump at any of a plurality of flow rates. Thenet positive suction head is preferably maintained by a the load sensinghydrostatic drive system.

The foregoing detailed description of the invention has been disclosedwith reference to specific embodiments. However, the disclosure is notintended to be exhaustive or to limit the invention to the precise formsdisclosed. Those skilled in the art will appreciate that changes couldbe made to the embodiments described above without departing from thebroad inventive concept thereof. Therefore, the disclosure is intendedto cover modifications within the spirit and scope of the presentinvention as defined by the appended claims.

We claim:
 1. A transportable high vertical-lift emergency water pumpingsystem for moving emergency water from a water source at a low elevationto a higher elevation, the pumping system comprising: a first pumphaving a first-pump suction port at the higher elevation; a second pumphaving a second-pump suction port at the low elevation and a second-pumpdischarge port in fluid communication with the first-pump suction port;a variable speed driver operatively coupled to the first pump; and aload sensing hydrostatic drive system operatively coupled to thevariable speed driver and to the second pump, the load sensinghydrostatic drive system configured to maintain a minimum net positivesuction head at the first-pump suction port sufficient to preventcavitation in the first pump when the variable-speed driver operates atany speed within a range of flows.
 2. The transportable highvertical-lift emergency water pumping system of claim 1, wherein thevariable speed driver is a diesel engine and the first pump isoperatively coupled to the diesel engine by a gear assembly.
 3. Thetransportable high vertical-lift emergency water pumping system of claim1, wherein the second pump is a submersible hydraulic pump and the loadsensing hydrostatic drive system is operatively coupled to thevariable-speed driver by a gear assembly.
 4. The transportable highvertical-lift emergency water pumping system of claim 3, wherein thehydrostatic drive system comprises a hydraulic pump operatively coupledto the gear assembly and a hydraulic motor in fluid communication withthe hydraulic pump and the submersible hydraulic pump.
 5. Thetransportable high vertical-lift emergency water pumping system of claim1, wherein the first pump is a fire pump, the second pump is asubmersible hydraulic driven pump and the first-pump suction port isconnected directly to the second-pump discharge port by a lay-flat hose.6. The transportable high vertical-lift emergency water pumping systemof claim 1, wherein the first pump has a first-pump efficiency and thesecond pump has a second-pump efficiency less than the first-pumpefficiency.
 7. The transportable high vertical-lift emergency waterpumping system of claim 1, wherein the second pump is a floatinghydraulically driven submersible pump.
 8. The transportable highvertical-lift emergency water pumping system of claim 1, wherein thesecond pump is an electrically driven submersible pump.
 9. Thetransportable high vertical-lift emergency water pumping system of claim1, further comprising a third pump having a third-pump suction port atthe low elevation and a third-pump discharge port in fluid communicationwith the first-pump suction port.
 10. The transportable highvertical-lift emergency water pumping system of claim 9, wherein thesecond and third pumps may independently be turned on or off so thateither the first pump or the second pump or both the first pump and thesecond pump may be used to increase lift or flow capacity.
 11. Thetransportable high vertical-lift emergency water pumping system of claim1 wherein the pumping system is mountable on a mobile platform.
 12. Amethod for moving emergency water from a water source at a low elevationto a higher elevation relative to the water source, the methodcomprising: drawing water from the water source into a suction port of ahydraulically driven submersible pump in the water source; dischargingthe water from a discharge port of the hydraulically driven submersiblepump into a lay-flat hose connecting the discharge port of thehydraulically driven submersible pump to a suction port of a fire pumpat the higher elevation; maintaining a minimum net positive suction headat the fire-pump suction port sufficient to prevent cavitation in thefire pump when the water is discharged from a discharge port of the firepump at any rate within a range of flow rates.
 13. The method forpumping emergency transportable water according to claim 12, furthercomprising the step of driving the fire pump and the submersible pumpwith a variable speed diesel engine.
 14. The method for pumpingemergency transportable water according to claim 13, further comprisingthe step of coupling the fire pump to the diesel engine with a gearassembly and coupling the submersible pump to the gear assembly with aload sensing hydrostatic drive system.
 15. The method for pumpingemergency transportable water according to claim 14, wherein the minimumnet positive suction head is maintained by the load sensing hydrostaticdrive system.